Manufacture of staple fiber yarns from continuous filaments



April 13, 1937. w. l. TAYLOR ET AL 2,077,079

MANUFACTURE OF STAPLE FIBER YARNS FROM CONTINUOUS FILAMENTS Original Filed May l8, 1934 FIG. 7

WILLIAM I- TAYLOR FRANK C- HALE ALFRED H-WQ Q QQUFF TORS AT TOR NEYS Patented Apr. 13, 1937 MANUFACTURE OF STAPLE FIBER YARNS FROM CONTINUOUS FILAMENTS William Ivan Taylor,

Frank Corbyn Hale, and

Alfred Herbert Woodrufl, Spondon, near Derby,

England, assignors to Celanese Corporation of America, a corporation of Delaware Original. application May 18, 1934, Serial No. 726,264. Divided and this application May 28, 1935, Serial No. 23,804. In Great Britain May 13 Claims.

This invention is a divisional of U. S. application 8. No. 726,264 filed 18th May 1934, and relates to the manufacture of spun or staple fiber yarn from continuous. filaments, i. e. filaments of considerable length as compared with the length of fiber required in the yarn to be produced or as compared with the short, naturally-occurring fibers such as, for example, cotton orwool, the object of the invention being to produce such yarn in which the physical characteristics of the original filaments are to a large extent retained, as well as to effect the production in a simple, expeditious, and cheap manner.

The formation of yarn containing staple fiber from continuous filaments is effected according to the invention by causing a bundle comprising a suitable number of filaments to pass in contact with the periphery of a cutting roller having sharp-edged flutes, the periphery of the 20 roller moving in the same general direction as the filament bundle and at a different. speed therefrom, and pressing the bundle against the periphery of the roller so that the flutes exert a cutting action on filaments in the bundle.

By reason of the relative motion between the filaments and the cutting surface, the filaments are readily cut with only a light pressure exerted on them at the cutting surface. There is, therefore, only a light gripping action on the bundle,

with the result that the filaments in the bundle are subjected to relatively low tension.

It will, therefore, be seen that the method of the present invention is not one relying on the drafting ofnaturally-occurring fibers or fibers already formed by a cutting or like operation. On the other hand, the invention does not apply to the filaments a tension suflicient to break them. In fact, eifecting the cutting of the filamentsby pressing them against the flutes of the cutting roller is particularly advantageous in that it allows substantial retention of the physical properties (and especially extensibility) of the filaments in their conversion to fiber.

The points of cutting are distributed among the filaments, the cut filaments being trans formed into fibersof an average length depending upon the frequency with which the filaments are cut. Such frequency, and consequently the average length of fiber, can be controlled by adjustment of various factors, e. g. by having a predetermined amount of twist in the bundle, as will appear later. Usually all the filaments in the bundle are transformed into staple fibers.

Movement of the surface of the fluted cutting roller in the same direction as the filaments asfilaments.

the surface having the cutting action is effected by means of a roller the periphery of which also moves in the direction of motion of the filaments so as to facilitate continued forward feed of the The pressing roller may move. at the same speed as the cutting roller or at a difierent speed therefrom. For example both rollers may be positively driven at a speed which provides, in relation to the speed of passage of the filaments between them, the necessary slipping action so as to promote the cutting of the filaments. The pressing roller may, however, be conveniently driven by its engagement with the rotating cutting roller, in which case itsspeed is controlled by the speed of the driven roller, and in some cases to some extent by the speed of passage of the filaments.

Cutting of the filaments can also be effected by an inversion of the arrangement just described, i. e. by employing a fluted cutting roller driven by contact with a positively driven roller not necessarily having any cutting action. In this case the cutting roller presses itself against the filaments. Both rollers may have a fluted cutting surface, suitable constructions of such an arrangement being described hereafter.

Since continuity'of the material as a whole must not be broken during the cutting of the filaments, the roller or rollers having the cutting action should not, under the pressure applied. sever more than one or relatively few of the filaments in the material at any point along the length of the material.

The bundle may be collected in any suitable manner. Thus, it may pass to a twisting and winding device which inserts twist while forming the bundle into any desired form of package. It is to be understood, however, that any twist originally in the bundle of filaments is not substantially removed by the operation of severing the filaments, and therefore remains in the bundle fed to the collecting device. Any additional twist imparted when collecting the bundle, as, for example, by winding the bundle by a cap or ring spinning device, is added to the remain-- der of such initial twist.

With the gripping device operating in asubstantially non-slipping manner, the filament bundle may be converted into a fibrous bundle at a rate substantially equal to the peripheral speed of these rollers. At the same time, while there is pressure exerted on the filaments at the cutting device, the filaments may be able to slip over the cutting surface at a rate which may be substantially the same as the rate of delivery of the product from the gripping device.

' die during the passage of the filaments from the cutting device to the gripping device.

The conversion may take place over a wide range of speeds, e. g. the fibrous product may be formed at a rate ranging from a few feet per minute up to 50, 75, 100, 150 or more yards per minute. The invention therefore provides for the production of a yarn containing staple fiber direct from continuous filaments in a very simple, rapid, and cheap manner. I

subjection of the material to more than one cutting device brings about a reduction in average fiber length. Thus, material produced by one passage through an apparatus as above described may be passed again through the same or another apparatus, the amount of twist imparted to the material after the first passage being suitably regulated to enable it to withstand the further cutting treatment.

Again, additional twist may be added in a separate operation. For many purposes, how ever, adequate twist can be inserted as the final step of the operation in which the filaments are converted into the yarn containing staple fiber. Thus, about 3 turns per inch may be added by a cap-spinning device to give a yarn particularly suited to use in knitting machines. In

fact, although such twist is quite low for a staple fiber material, the strength of the yarn is quite considerable, probably due to longer fibers being mixed with shorter ones.

-The carrying out of the invention will now be described by way of example with reference to the accompanying diagrammatic drawing, in

which .Fig. 1 shows a cutting=noller device and a gripping-roller device disposed substantially horizontally with respect to each other;

Fig. 2 shows a cutting-roller device and a gripping-roller device disposed substantially vertically one above the other;

Fig. 3 shows a modified form of apparatus also utilizing a vertical disposition of the roller pairs;

i Fig. 4 is a detailed view of the cutting roller pair;

Fig. 5 shows a modified cutting device; and Fig. 6 is a front elevational view of the rollers showing the fluted cutting surfaces.

Referring to Fig. 1, a bundle of filaments I0 01' denier in accordance with the denier of the products desired is fed between a pair of rollers ll, l2 and then between a further pair of rollers ll, ll. The roller H is provided with smooth flutes and the roller I3 is covered with rubber or the like and aultabLv loaded so that the two rollers firml grip the bundle. The roller I2 is provided with a cutting surface of sharp-edged flutes. 'lne roller l l lightly presses the bundle l0 against the periphery of the roller I2.

The roller i4 is driven at a speed in excess of that of the roller l2 so that by reason of the firm grip exerted between the rollers l3, It the bundle I0 is caused to slip over the periphery of the cutting roller l2. There is light pressure between the rollers II and I2 and the slip permitted by these rollers, and the bundle drawn between the rollers has its filaments severed at frequent intervals so that after leaving the rollers ll, l2 the bundle contains staple fibers, the protruding ends of which are diagrammatically indicated in the figure.

The rollers ll, l3 may rotate solely by their contact with the driven rollers l2, I4, it being understood, however, that an inversion of the roller arrangements is possible; for example the cutting roller l2 may rest upon and be driven by its contact with the non-cutting roller ll. Again, both rollers ll, l2 may provide a cutting action.

Referring now to Fig. 2, the filament bundle I0 is shown supplied from a bobbin l5 and led to a pair of rollers ll, l2 as described with reference to Fig. 1. Gripping rollers l3, H are disposed below the roller l2 so that the bundle l0 passes over an arc of the roller l2 and vertically downwards to the nip of the rollers l3, Hi. The roller I3 is carried on an arm l8 pivoted at l9 and is pressed against the roller M by a cord 20 attached to the arm and carrying a weight 2| suflicient to provide the gripping and preferably non-slipping action of the rollers l3, l4.

The arrangement of Fig. 2 thus provides the application of any desired amount of pressure at the pair of gripping rollers, while allowing for an independent amount of pressure being exerted between the rollers II, l2. Thus, the roller H can be self-loaded as shown in Fig. 4, the roller having a spindle 22 working in a slotted bearing 23 so that the roller ll rests by its own weight on the roller l2.

The roller ll may be rigid and so formed as to have the desired weight for the loading required, or it may consist of a resilient core 24, e. g. of sponge rubber or other soft rubber, within -a flexible sheath 25, e. g. of thin metal tubing which provides a hard though flexible surface by which the filaments are pressed against the cutting periphery of the roller i2.

The cutting roller is made of steel or other hard material having flutes running generally transverse to the direction of motion of the filaments, e. g. helical flutes as shownat 34 in Fig. 6. These flutes have sharp edges over which the filaments are drawn as they slip between the cutting roller and the pressing surface. For exam-- ple, the roller may have semi-circular, triangular, or rectangular flutes forming with the surface of the roller a clean edge against which the filaments are pressed. The cutting roller 35 shown in Fig. 6 is driven by its shaft 36 with the desired speed and in the required direction, and the pressing roller 31 is driven by its contact with the roller 35. The roller 31 is shown fluted to form a cutting surface, the helical flutes of one roller crossing those of the other at an angle at their points of contact.

In Fig. 3, the bundle 'i0 is supplied from a rotating bobbin I6 so as to add twist to the bundle before it is subjected to the action of the cuttingdevice. Both rollers H, i3 are arranged to be pressed against their corresponding rollers I2, I 4 by the cord and weight arrangement 20, 2|. For this'purpose the rollers ll, l3 are mounted on a bar 26 pivotally mounted at 21 on 5 the arm l8, the point 28 (preferably adjustable) at which the cord 20 is attached to the bar 26 being such that the requisite pressures may be ex erted by the rollers ll, l3 to provide for the a cutting action of the one roller pair and the gripping action of the other respectively.

In Fig. 2 the yarn containing the staple fiber is shown being collected by a cap spinning device 29 operating to insert any desired amount of twist. In Fig. 3 collection is effected by a ringspinning device 30. If desired, the yarn may be lubricated before being twisted, for example by carrying it over a wick I28, roller or other device supplied with lubricant and arranged between the rollers l3, l4 and the balloon guide 20 3| of the twisting device. Again, lubricant may be sprayed on to the yarn. 'I'he distance between the rollers ll, l2 and the gripping rollers l3, I4 is such that the rollers l3, l4 take control of the fibrous bundle soon after cutting so as to feed it continuously to the collecting device.

In Fig. 5, the bundle I is carried into slipping contact with the cutting roller I 2 by means of gripping rollers l3, l4 and the filaments are pressed against the roller l2 by the surface of a stationary member 32 suitably weighted and carried in a slotted bearing 33 so as to rest on the roller l2. By reason of the pressure applied and the slippage of the bundle between the roller I2 and the member 32, the roller l2 cuts fila-' ments in the bundle at frequent intervals.

The average length of staple fiber has an important bearing on the appearance and other qualities of the product produced according to 40 the invention. This may be controlled by suitable adjustment of the apparatus and its conditions of operation, as well as by selection of the filaments to be treated. Thus, in general, a higher rate of operation of the apparatus re- 45 suits in a longer average fiber length being obtained. A greater amount of twist in the filament bundle tends to reduce the average fiber length. Again, greater pressure at the cutting device (this pressure depending also upon the 50 size of the filament bundle to be treated) reduces the average fiber length, as also does an increase in the ratio between the speeds of the feeding and cutting devices. Finer filaments are usually more readily cut, and the more fre- 5 quent breakage has the effect of reducing the average fiber length.

As indicated above, greater pressure at the cutting device is necessary with increase in the size of the filament bundle. Finer filaments,

60 however, require less pressure than coarser filaments, Again, a lower ratio between the speeds of the feeding and cutting devices calls for higher pressure.

As regards the eifect of the distance between 65 the cutting and gripping devices on the length of staple, it may be noted that at the most only a small percentage of the fibers in the staple fiber yarn are less in length than this distance.

I What we claim and desire to secure by Letters ,70 Patent is:

1. Process for the conversion of continuous filaments directly into a continuous product containing staple fiber, which comprises causing a bundle of continuous filaments to pass in contact with 75 the surface of a fluted cutting roller moving in substantially the same direction as said filaments but at a peripheral speed difi'erent from the speed of the filaments, and pressing the bundle against the surface of the roller so that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at said point to a cutting action that at any one point severs part only of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments.

2. Process for the conversion of continuous filaments directly into a yarn containing staple fiber, which comprises causing a twisted bundle of continuous filaments to pass in contact with the surface of a fluted cutting roller moving in substantially the same direction as said filaments but at a peripheral speed different from the speed of the filaments, and pressing the bundle against the surface of the rollerso that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at said point to a cutting action that at any one point severs part only of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments. I

3. Process for the conversion of continuous filaments directly into a yarn containing staple fiber, which comprises causing a bundle of continuous filaments to pass in contact with the surface of a fluted cutting roller moving in substantially the same direction as said filaments but at a peripheral speed diiferent from the speed of the filaments, pressing the bundle against the surface of the roller so that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at said point to a cutting action that at any one point severs part only of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments and collecting the treated bundle as a yarn by a twisting and winding operation.

4. Process for the conversion of continuous filaments directly into a continuous product containing staple fiber, which comprises causing a bundle of continuous filaments to pass in contact with the surface of a fluted cutting roller moving in substantially the same direction as said filaments but at a peripheral speed difierent from the speed of the filaments, and pressing the bundle against the surface of the roller by the surface of a second fiuted cutting roller so that the bundle is continuously nipped substantially at a point in its length and is subjected on two sides at said point to a cutting action that at any one point severs only part of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments.

5. Process for the conversion of continuous filaments directly into a continuous product containing staple fiber, which comprises causing a bundle of continuous filaments to pass between a stationary surface and the surface of a fluted cutting roller moving in substantially the same direction as said filaments but at a peripheral speed difl'erent from the speed of the filaments, and applying pressure to the bundle'by the stationary surface in such a manner that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at said point to a cutting action that at any one point severs part only of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments.

6. Process for the conversion of continuous filaments directly into a continuous product containing staple fiber, which comprises drawing a bundle of continuous filaments over the surface of a fluted cutting roller moving at a less speed than the filaments but in substantially the same direction, and pressing the bundle against the surface of the roller so that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at said point to a cutting action that at any one point severs part only of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments.

7. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a rotatable fluted cutting roller, means for causing a bundle of continuous filaments tomove over said roller. means with which the fluted surface of the roller forms a nip at a point in the length of the surface of the roller, considered in the direction of movement of the surface of the roller, to keep the filaments continuously pressed against the fiuted sur face substantially at a point in the length of the filaments, and means for causing the roller to rotate so that itssurface moves in substantially the same direction as the bundle but at a speed different from that of the bundle.

8. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a rotatable helically fluted cutting roller, means for causing a bundle of continuous filaments to move over said roller, means with which the fluted surface of the roller forms a nip at a point in the length of the surface of the roller, considered in the direction of movement of the surface of the roller, to

keep the filaments continuously pressed against the fluted surface substantially at a point in the length of the filaments, and means for causing the roller to rotate so that its surface moves in substantially the same direction as the bundle but at a speed different from that of the bundle.

9-. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a rotatable fluted cutting roller, means for causing a bundle of continuous filaments to move over said roller, a rotatable roller with which the fiuted surface of the roller forms a nip to keep the filaments continuously pressed against the fluted surface substantially at a point in the length of the filaments, and means for causing the roller to rotate so that its surface moves in substantially the same direction as the bundle but at a speed different from that of the bundle.

10. Apparatus according to claim 9 wherein the pressing roller has a surface comprising a, flexible metal tube.

11. Apparatus according to claim 9 wherein the pressing roller comprises a flexible metal tube and a resilient core on which the tube is mounted.

12. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a pair of contacting rollers, at least one of which is a fluted cutting roller, lightly pressed together to form a nip, a further pair of rollers firmly pressed together, and means to drive at least one of each pair of rollers, so that the second pair of rollers move with a peripheral speed greater than the first pair of rollers, the second pair of rollers being adapted to grip a bundle of continuous filaments and pull the bundle through the nip of the cutting pair of rollers at a speed different from the speed of the surfaces of said rollers.

13. Apparatus for the conversion of continuous filaments directly into yarn containing staple fiber, comprising a rotatable fluted cutting roller, means for causing a bundle of continuous filaments to move over said roller, means with which the fluted surface of the roller forms a nip at a point in the length of the surface of the roller, considered in the direction of movement of the surface of the roller, to keep the filaments continuously pressed against the fluted surface substantially at a point in the length of the filaments, means for causing the roller to rotate so that its surface moves in substantially the same direction as the bundle but at a speed different from that of the bundle, a twisting and winding device to collect the treated bundle and a lubricator disposed between the second pair of rollers and the twisting and winding device so as to contact with the bundle.

WILLIAM IVAN TAYLOR. FRANK CORBYN HALE. ALFRED HERBERT WOODRUFF. 

